There is a known endoscope, catheter, or manipulator having a system in which a bending portion or a movable portion, such as forceps, disposed at the distal end of an insertion portion is driven by means of a wire (for example, see Patent Literatures 1 and 2).
In these Patent Literatures 1 and 2, a long, flexible insertion portion, in which the outer circumference of a flexible multilumen tube is covered with a coil tube, is employed, a wire is guided so as to penetrate through a lumen formed in the multilumen tube, and the coil tube enables torque transmission.